A known torque fluctuation absorber such as a damper is disclosed in JP2002-13547A. The damper for a hybrid drive apparatus disclosed includes a damper mechanism for absorbing a driving torque fluctuation of a flywheel fixed to a drive shaft of a drive source, and a limiter mechanism arranged on an outer circumferential side of the damper mechanism. The limiter mechanism is achieved by a direct or indirect (i.e. by means of a friction surface plate) pressure contact between the flywheel and a friction material fixed to the outer circumferential portion of the damper mechanism. When a fluctuation torque reaches a predetermined value (i.e. limit torque value), the damper mechanism is allowed to slip so that an excess torque is prevented from being input or transmitted to a transmission.
However, according to the aforementioned torque fluctuation absorber with the known limiter mechanism, a downsizing of the device is difficult for ensuring a required limit torque value. In addition, a great number of friction materials and high accuracy disc springs are required, which may lead to a high cost.
Thus, a need exists for a torque fluctuation absorber that can include an excess torque restriction mechanism in substitution for a limiter mechanism and that can achieve a downsizing and a low cost.